The epoch of doubt and transition during which the Greeks passed from the dim fancies of mythology to the fierce light of science was the age of Pericles, and the endeavour to substitute certain truth for the prescriptions of impaired authorities, which was then beginning to absorb the energies of the Greek intellect, is the grandest movement in the profane annals of mankind, for to it we owe, even after the immeasurable progress accomplished by Christianity, much of our philosophy and far the better part of the political knowledge we possess.